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What are types of Corrosion Inhibitor (Filmer) and neutralizing amine used in crude distillation units. What is the philosophy of their work and the concentration of injection?

Nov-2023

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sam lordo, Becht, salordo@comcast.net

Neutralisers are amine based and are used to neutralise acidic species.. there are a number of amine neutralisers that can be used.. Characteristics of the neutraliser are:

- Stronger than ammonia.
- Does not form a solid salt within 25 deg F of the ovhd temperature.
- Atomised into the over-line using a nozzled quill (steam works well for the atomisation medium).

Filming amine are added to coat the metal surfaes to keep them free of deposits and oil wetted. Characteristics of the filmer are:

- Oil based add with a hydrocarbon diluent (reflux) at a 100-200 : 1 dilution ratio.
- Oil based filmer need to be injected with a nozzled spray quill. preferably), slotted quills can be used.
- Water based filmers can be used when using water wash and injected into the water.
- Filmer should not increase the emulsion tendencies in overhead accumulator or increase the MSEP of Jet.

Always recommend a proper overhead water wash to prevent any salting in the overhead circuits and equipment

Jul-2024
Alexander Vartapetyan, ARBADOX CHEMICALS, alexander.vartapetyan@arbadox.com

No one protection technology will work if the crude oil contains a lot of Cl-salts. Therefore, the first stage of corrosion protection is high-quality oil desalting on EDU with demulsifier.

The second important stage is the supply of the neutralizer. An important point is the choice of the safest amine-type neutralizer, because it must have proven safety in terms of the formation of choride salts (amine hydrochlorides).

The third stage is the supply of an amide-type film-forming inhibitor. It must be safe from the point of view of deposits formation and a negative impact on the quality of gasoline (not cause an increase in nitrogen content).

The fourth most important stage is monitoring of drainage water (in terms of pH (normally 5.5-6.5, but there are exceptions, depending on the type of oil); content of dissolved iron (not higher than 1.0 mg/l); corrosion rate of control samples - coupons (not higher than 0.1 mm/year). ARBADOX company produces a full range of the above reagents.

Jun-2024
Salem Ghoul, Mellitah O&G Co, smghoul@gmail.com

pH 5.5 to 6.5 ,over 7 Deposits may occur due to ammonia and/or amine chloride salts.

Crude feed less than 1 PTB.

Chloride at water sample less than 20 ppm.

monitoring Fe at water sample.

W/L CC.

Chemical Dosage based on pH at condensate drained water.

Mar-2024
Joan de la Paz, Baker Hughes, joan.paz@bakerhughes.com

Corrosion Inhibitor protection mechanisms are the formation of a protective layer between the bare metal and the fluid to minimize the corrosion reaction. there are several chemistries and also can be water or oil soluble. Is really important to have a preliminary survey of the unit before starting a treatment Also is important in the final efficiency of the treatment how this CI is applied. regarding the neutralizing amines the target is to react with the HCL formed at the very initial Dew Point and help to keep the pH at the accumulator in the range of 5.5-6. all chemistries are amine based but there are many composition then also a survey of the unit and process conditions is needed in order to minimize the Salt formation risk.

Nov-2023
Marcio Wagner da Silva, Petrobras, marciows@petrobras.com.br

According to the characteristics of the processed crude, the performance of desalters needs to be optimized, especially considering the concentration of magnesium and calcium chloride salts which tends to suffer hydrolysis and generate HCl which will concentrates in the overhead system of the atmospheric column, this is a special concern to refiners processing heavy crudes, slop blended with crude oil, and opportunity crudes.

Some refiners adopt an online injection of corrosion inhibitor in the overhead systems to control the salts precipitation. Normally, the corrosion inhibitor applied is a kind of filmic amine like alkylene polyamines (ethylene diamine - EDA, for example) which produces a protective film inside of the critical areas of the atmospheric column and neutralize the acid affect of decomposed salts from the crude oil.

Regarding the concentration of the corrosion inhibitor this vary case by case due to the characteristics of the processed crude, crude oils with high contaminants content and poor desalting performance like heavy and slop crudes tends to present higher concentration of NH3, HCl and amines in the desalted crude oil which raises the probability of corrosion and demands higher flow rates of corrosion inhibitor, it's recommended to look for specialized advice from a chemical treating company which will optimize the system to control de corrosion process under minimum flow rate of corrosion inhibitor as well as indicate what is the best corrosion inhibitor for your processed crude oil blend.

Nov-2023